how come Matlab give me the result corr(u,v)=-1 u=[1 0]' and v=[0 1]' (i.e., two orthogonal column vectors, basis of the Euclidean plane ...)
Suddenly this makes no sense to me ... their scalar product = 0 ... they should be perfectly UNcorrelated?
i know it works out to -1 with the correlation formula $dot((x-mean(x)),(y-mean(y))/(norm(x)*norm(y))$ but could someone enlighten me ? (it's very frustrating ... i seem to miss something (and I have been working with such things for a while...)
To summarize: why (logical understanding point of view) are they negatively perfectly correlated (-1) whereas I would expect them to be perfectly UNCORRELATED (0) ?